By Bob Tuzik • January, 2007 Friction control plays a major role in reducing wear, noise and vibration, and managing wheel/rail interaction on rail transit systems. Controlling friction has become more achievable with the advent of engineered friction modifiers and improvements to wayside and onboard application systems for both traditional lubricants …
By Roy E. Smith • March, 2006 The introduction of new, low-floor vehicles into existing North American transit systems has provided an attractive means of meeting current operating requirements. By the same token, their introduction has created a number of vehicle/track compatibility issues—particularly when these modern cars are introduced into older …
by Bob Tuzik • April 10, 2005 Rail Grinding has been used to solve a host of problems on transit systems. It recently was used in Boston to remove a new wrinkle. A specialized grinding program was initiated in 2002 on the heels of a series of light-rail derailments on the …
by Bob Tuzik, January 1, 2005 Any problem affecting the New York City Transit is by default a big problem. The process of transporting more than four million passengers per day in 6,000 vehicles on more than 700 miles of elevated, underground at-grade mainline tracks, on a system that operates 24 hours …
by Bob Tuzik February 1, 2005 There are two primary approaches to friction management on rail transit systems: onboard and wayside. The most effective method depends upon the demands of the system. A relatively small system with consistent degrees of curvature, for example, might lend itself to onboard application. A system with …
by Bob Tuzik, January 1, 2005 When NYCTA wanted a new fastener that was 35% “softer” than the softest DF fastener it had in use, a fastener that would not raise the track by more than 1-1/8 inches (30 mm), Dynamic Engineering designed the APT-BF system. The APT-BF fastener incorporates two elastic …
by Bob Tuzik, December 1, 2004 Investigations have shown that wheel-flange/gauge-face angle and the coefficient of friction (COF) play significant roles in contributing to or preventing flange-climb derailments. Investigations have also shown that Light Rail Vehicles with Independently Rotating Wheels (IRWs) have a greater propensity for flange-climb derailment than vehicles with conventional …
by Bob Tuzik, December 1, 2004 As part of its effort to monitor dynamic vehicle/track interaction on the Northeast Corridor, Amtrak commissioned ENSCO, Inc., to develop a Wayside Train/Track Interaction Detection System. The goal was to measure and collect information on vehicle/track forces that would enable Amtrak to determine the causes of …
By Bob Tuzik • November 4, 2004 If the first unwritten rule in optimizing the wheel/rail interface on rail transit is: Know your system; the second rule should be: Recognize that the w/r interface is a system. “No single department can attack the issues in isolation and expect to get very far,” Joseph Oriolo, Senior …
by Eric E. Magel • September 20, 2004 Wheel wear is an inevitable byproduct of wheel/rail interaction. Excessive wear, however, indicates an imbalance in some aspect of the wheel/rail interface. Amtrak’s high-speed Acela trains, running on track with much greater curvature than other high-speed systems, were quickly found to exhibit very …